Effects of stocking density on growth, gross composition, and plasma and hepatic metabolite levels in palmetto bass, Morone saxatilis x M. chrysops

Juveniles of palmetto bass, Morone saxatilis x M. chrysops, were stocked at low (0.7 kg/m(3)), medium (1.4 kg/m(3)) and high (2.8 kg/m(3)) densities. Fish were held in 2.4-m(3) tanks and fed to satiation twice daily with floa ting pelleted feed for an 84-day rearing period. The highest percent weight gain and specific growth rate were obtained in fish raised at medium stock ing density; significant differences were found only between low and medium stocking densities. Both the food intake and specific growth rate declined during the course of the experiment. The relationship between proximate co mposition and growth of fish is less apparent; however, fish with good grow th (at medium stocking density) contained more lipid, whereas those with po or growth (at low density) had lower lipid content. The correlation between growth rate and stocking density may be dependent on social interactions, physical constraints, and threshold level of stocking density. The prelimin ary results of the relationship between plasma and hepatic metabolite level s and stocking densities are also shown.